| Corncob to value-added chemical transformation by metal/beta zeolite and metal/mesoporous SBA-15 catalytic pyrolysis | |
| Jeenpadiphat S., Kasiban C., Tungasmita D.N. | |
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| BACKGROUND: Although the pyrolysis of biomass has been investigated by many researchers, there are no data available regarding conversion to value added ester compounds from catalytic corncob pyrolysis at low temperature. In this present research thermal and catalytic cracking of residue corncob was performed at 250 to 600 °C under N2. The performance of two acidic porous catalysts, metal-beta zeolite and mesoporous SBA-15, with different metal (Al, Pd and Ni) loadings, were compared with the non-catalytic reaction. RESULTS: The cracking products were classified into gases, liquid and char. Methane, C5 + and CO2 were the main gas products, while light ester derivatives were the main components in the liquid fraction and these can be important intermediate chemicals. The phenolic compounds were obtained when using low thermal pyrolysis. A reaction temperature of 300 °C with the Al-SBA-15 catalyst at a SiO2/Al2O3 mole ratio of 20 was found to be optimal in terms of producing the highest biomass conversion with a high proportion of light esters. CONCLUSION: The Al-SBA-15 (20) catalyst was selective towards producing the light ester 2-methoxy phenyl acetate (59.4%), which is an important intermediate chemical for production of sweet fruity aromas in the food industry. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry | |
| keywords | |
| Aluminum; Bioconversion; Biomass; Carbon dioxide; Catalysis; Catalysts; Cracking (chemical); Cracks; Data handling; Esters; Liquid methane; Low temperature engineering; Metals; Palladium; Pyrolysis; Temperature; Zeolites; Catalytic pyrolysis; Corncob; Intermediate chemicals; Non-catalytic reactions; Phenolic compounds; Reaction temperature; SBA-15; Value-added chemicals; Catalytic cracking; 4 ethylphenol; alcohol derivative; aluminum; carbon; carbon dioxide; cellulose; ester derivative; furan derivative; guaiacol; hemicellulose; lignin; mesoporous silica nanoparticle; methane; nickel; palladium; phenol derivative; volatile agent; zeolite; Article; biomass conversion; controlled study; low temperature; maize; nanocatalyst; physical chemistry; pyrolysis; scanning electron microscopy; surface area; temperature; thermostability; X ray diffraction | |
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| Seashell-derived mixed compounds of Ca, Zn and Al as active and stable catalysts for the transesterification of palm oil with methanol to biodiesel | |
| Jindapon W., Jaiyen S., Ngamcharussrivichai C. | |
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| Heterogeneous base catalysts, composed of mixed calcium, zinc and aluminium compounds (ZSA), for the transesterification of palm oil with methanol to produce biodiesel as fatty acid methyl esters (FAME) were prepared from waste mixed seashells in the presence of zinc nitrate and alumina via dissolution-precipitation method. The effects of the catalyst calcination temperature on the physicochemical and catalytic properties were studied. Calcination of ZSA at 300 °C generated calcium hydroxide as the main active phase, while the formation of CaO at higher calcination temperatures contributed to the catalyst basicity and catalytic activity. The catalyst calcined at 500 °C (ZSA-500) possessed a calcium-rich surface on which nanocrystallites of CaO were dispersed. The ZSA-500 catalyst showed the highest stability to ambient air (relative humidity of 73%) exposure for 3 d. The loss of catalytic activity at the higher calcination temperatures of 700 and 900 °C was related to the formation of Ca12Al14O33 and the transformation of CaO to calcium carbonate during air exposure. The ZSA-500 catalyst had the highest surface area and basicity and gave the highest FAME yield (98.0 ± 1.60 wt%). Suitable conditions for transesterification over ZSA-500 at 60 °C were a catalyst loading of 10 wt%, methanol:oil molar ratio of 30:1 and reaction time of 3 h. Moreover, the ZSA-500 catalyst could be reused after methanol washing to give a FAME yield more than 96% for at least five uses. © 2016 Elsevier Ltd. All rights reserved. | |
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| Alumina; Aluminum; Biodiesel; Calcination; Calcium; Calcium carbonate; Catalysts; Fatty acids; Lime; Methanol; Oil shale; Palm oil; Precipitation (chemical); Transesterification; Zinc; Calcination temperature; Catalyst calcination; Catalytic properties; Dissolution precipitations; Fatty acid methyl ester; Heterogeneous base catalyst; Seashells; Suitable conditions; Catalyst activity | |
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| Poly(styrene)- and Poly(styrene-co-methyl methacrylate)-graft-hydrogenated natural rubber latex: Aspect on synthesis, properties, and compatibility | |
| Sakorn S., Rempel G.L., Prasassarakich P., Hinchiranan N. | |
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| The undesirable properties of natural rubber (NR) can be improved via hydrogenation and graft copolymerization. Hydrogenated NR (HNR) latex was prepared via diimide reduction and then grafted with styrene (ST) or ST/methyl methacrylate (MMA) to form poly(ST)-graft-HNR (poly(ST)-g-HNR, GHNRS) or poly(ST-co-MMA)-g-HNR (GHNRSM), respectively. For the grafting of ST monomer onto HNR particles, the %monomer conversion and %grafting efficiency (%GE) were monitored as functions of %hydrogenation, monomer and initiator concentrations, temperature, and time. Under the optimum condition (HNR with 54.3% hydrogenation; 100 phr of ST, 1 phr of initiator at 50°C for 8 h), maximum %conversion and %GE of 44.6% and 36.9%, respectively, were achieved. Thermogravimetric analysis revealed that the HNR grafted with ST or ST/MMA had higher decomposition temperature than an ungrafted one. When these graft products were blended at 10% (w/w) with acrylonitrile-butadiene-styrene (ABS) resin, the GHNRS/ABS and GHNRSM/ABS composites exhibited the higher flexural strength and heat aging tolerance compared to the ungrafted HNR/ABS composite. Scanning electron microscopy (SEM) also showed the higher degree of homogeneity at the fractural surface, supporting the higher compatibility between the ABS and the GHNRS or GHNRSM phases in the blends. J. VINYL ADDIT. TECHNOL., 22:100-109, 2016. © 2014 Society of Plastics Engineers. | |
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| Acrylic monomers; Esters; Grafting (chemical); Hydrogenation; Latexes; Monomers; Rubber; Scanning electron microscopy; Styrene; Thermogravimetric analysis; Acrylonitrile butadiene styrene; Decomposition temperature; Graft co polymerizations; Grafting efficiency; Initiator concentration; Methyl methacrylates; Monomer conversions; Natural rubber latex; ABS resins | |
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| Antidegradation and reinforcement effects of phenyltrimethoxysilane- or N-[3-(trimethoxysilyl)propyl]aniline-modified silica particles in natural rubber composites | |
| Tunlert A., Prasassarakich P., Poompradub S. | |
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| The modification of silica particles with phenyltrimethoxysilane or N-[3-(trimethoxysilyl)propyl]aniline via a sol-gel reaction was performed in order to improve the dispersion of silica and antidegradation in natural rubber (NR). The functional groups on the modified silica surface were characterized by Fourier transform infrared spectroscopy, while the morphology was evaluated by scanning and transmission electron microscopy. The surface properties and antioxidant activity of the modified silica particles were determined by the water contact angle and 2, 2-diphenyl-1-picrylhydrazyl assay, respectively. The modified silica particles exhibited a higher hydrophobicity and a decreased interfacial adhesion energy compared with the unmodified silica particles. The modified silica particles were then incorporated into NR. The better dispersion of the modified silica particles than the unmodified ones in the NR matrix resulted in improved mechanical properties in terms of the modulus at 300% elongation (2.9 ± 0.02 MPa), hardness (52.5 ± 0.2 Shore A), abrasion resistance (241 ± 8 mm3) and compression set (20.2 ± 0.6%). In addition, the inclusion of the modified silica particles in the NR matrix gave a high initial temperature of decomposition and retarded the ozone-induced degradation compared with the NR filled with unmodified silica particles. © 2016 Elsevier B.V. | |
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| Aniline; Composite materials; Cracks; Dispersions; Fourier transform infrared spectroscopy; High resolution transmission electron microscopy; Mechanical properties; Rubber; Scanning electron microscopy; Sol-gels; Synthesis (chemical); Transmission electron microscopy; Transmissions; 2 ,2-diphenyl-1-picrylhydrazyl; Anti-oxidant activities; Interfacial adhesion energy; Modification of silica particles; Modified silica particles; Natural rubber composites; Phenyltrimethoxysilanes; Scanning and transmission electron microscopy; Silica | |
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